And then of course you have those rare issues where the fault is actually dangerous! Just a few years ago I called an electrician to my house because the breaker for the laundry room light fixtures was tripping every time, so I suspected a short. The electrician who showed up (hell of a guy, loved to chat!) said the ceiling light fixture was wired incorrectly and the housing was live! A quick and easy fix for him but anyone changing a lightbulb on that socket over the past 30 years was risking a shock!

Of course this is only 120V AC so not the deadliest thing in the world, but it’s always fascinated me that a fault can go unnoticed for many many years and still pose a hazard. It’s kind of like WW2 munitions or something, but completely unintentional!